1. Technical Field
The present invention relates to a method for operating a wind energy installation, in particular for adapting a wind energy installation to given wind conditions, the wind energy installation having a rotor, which can be driven by wind, with at least one rotor blade, and having a generator for converting the mechanical energy of the rotor to electrical energy. Furthermore, the invention relates to a method for operating a windpark comprising such wind energy installations and to a wind energy installation having a control/regulation device for carrying out the abovementioned method.
2. Prior Art
It is known to regulate wind energy installations depending on given wind conditions or to drive individual components of the wind energy installation depending on the wind conditions. It is known, for example, to arrange a wind vane at the rear end of a pod of a wind energy installation, i.e. on the side of the wind energy installation remote from the wind. Depending on the wind direction determined by means of the wind vane, in this case in particular the so-called yaw drive mechanism of the wind energy installation is regulated. In this case, the rotor of the wind energy installation tracks the present wind direction by means of corresponding motors, with the result that, as much as possible, it is at right angles to the present wind direction. One disadvantage with the measurement of the wind using the rear end of the pod is in particular the fact that the wind conditions present there are severely influenced by the rotor, in particular the rotor blades, which is arranged upstream of the wind vane based on the wind flow. The wind conditions at the location of the wind vane therefore often do not correspond to the wind conditions at the location of the rotor blades or directly in front of the rotor blades. The result of this is the fact that the regulation of the wind energy installations is often not optimal.
Furthermore, a method for adapting a wind energy installation to existing wind conditions is known from the prior art in which, depending on the present power output of the wind energy installation, i.e. at least indirectly depending on the present wind conditions at the location of the rotor blades, the angle of incidence on individual or all of the rotor blades of the wind energy installation is adjusted. In this case, in one embodiment of this prior art, at high wind speeds which, in the worst case scenario, could lead to destruction of the rotor blades of the wind energy installation, and therefore in the case of a critically high power output of the wind energy installation, the rotor blades are rotated about their respective longitudinal axis in order to provide less resistance to the wind and to avoid damage. One disadvantage with this prior art is in particular the inertia of the method. The wind energy installation only responds to changing wind conditions when the corresponding wind fronts or gusts of wind have already reached the rotor blades of the installation and have already resulted in a certain, possibly even critical increase in the power output of the wind energy installation. For example, sudden, particularly strong gusts of wind or turbulences can in this case result in destruction of the installations since they are only registered when they have already reached the rotor blades of the installation.